8 research outputs found

    Effect of Spirulina platensis extract on growth potential of in vitro culture pear

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    Pears are among the most economically important fruits in the world that are grown in all temperate zones. ‘Le-Cont’ rootstock pear is one of the gene sources used to improve fruit productivity, rootstock resistance, and tolerance to biotic and abiotic stresses. Traditional propagation of pear. Pear is time-consuming and limited by a short growing season and hard winter conditions. Therefore, in vitro propagation is a suitable alternative method. Murashige and Skoog medium (MS) and spirulina platensis extract at 5,10 and 20 % supplemented with different concentrations (0.25, 0.5 and 1.0 mg/l) of 6-benzyladenine (BA) and kinetin (Kin), individually or in combination with them. Treatments were used for in vitro shoot proliferation. Nodal segments were used as explants. MS medium augmented was 3mg/l 6-benzyladenine (BA) plus 20 % Spirulina platensis extraction then used for shootlets proliferation of micro-shoots. A combination of 3 mg/l BA and 20 % Spirulina platensis as a growth media resulted in a significant improvement in shoot proliferation. This combination produced the highest number of shoots (2.8 per explant) and leaves (6.3 per explant) similar with those containing MS media plus 20% extraction (2.9 per explant) and leaves (6.8 per explant). The longest shoots (2.97 cm) were obtained in each previous treatment. However, these shoots were similar with those produced from classical multiplication by MS according to ISSR analysis which scored 89.1 % of mono morphism percentage and 10.1 % polymorphism. The ISSR analysis shows the highest similarity index percentage for P5-P9 0.986301

    The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

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    INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

    Tackling Cancer Resistance by Immunotherapy: Updated Clinical Impact and Safety of PD-1/PD-L1 Inhibitors

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    Cancer therapy has been constantly evolving with the hope of finding the most effective agents with the least toxic effects to eradicate tumors. Cancer immunotherapy is currently among the most promising options, fulfilling this hope in a wide range of tumors. Immunotherapy aims to activate immunity to fight cancer in a very specific and targeted manner; however, some abnormal immune reactions known as immune-related adverse events (IRAEs) might occur. Therefore, many researchers are aiming to define the most proper protocols for managing these complications without interfering with the anticancer effect. One of these targeted approaches is the inhibition of the interaction between the checkpoint protein, programmed death-receptor 1 (PD-1), and its ligand, programmed death-ligand 1 (PD-L1), via a class of antibodies known as PD-1/PD-L1 inhibitors. These antibodies achieved prodigious success in a wide range of malignancies, including those where optimal treatment is not yet fully identified. In this review, we have critically explored and discussed the outcome of the latest PD-1 and PD-L1 inhibitor studies in different malignancies compared to standard chemotherapeutic alternatives with a special focus on the clinical efficacy and safety. The approval of the clinical applications of nivolumab, pembrolizumab, atezolizumab, avelumab, and durvalumab in the last few years clearly highlights the hopeful future of PD-1/PD-L1 inhibitors for cancer patients. These promising results of PD-1/PD-L1 inhibitors have encouraged many ongoing preclinical and clinical trials to explore the extent of antitumor activity, clinical efficacy and safety as well as to extend their applications

    Effect of

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    Pears are among the most economically important fruits in the world that are grown in all temperate zones. ‘Le-Cont’ rootstock pear is one of the gene sources used to improve fruit productivity, rootstock resistance, and tolerance to biotic and abiotic stresses. Traditional propagation of pear. Pear is time-consuming and limited by a short growing season and hard winter conditions. Therefore, in vitro propagation is a suitable alternative method. Murashige and Skoog medium (MS) and spirulina platensis extract at 5,10 and 20 % supplemented with different concentrations (0.25, 0.5 and 1.0 mg/l) of 6-benzyladenine (BA) and kinetin (Kin), individually or in combination with them. Treatments were used for in vitro shoot proliferation. Nodal segments were used as explants. MS medium augmented was 3mg/l 6-benzyladenine (BA) plus 20 % Spirulina platensis extraction then used for shootlets proliferation of micro-shoots. A combination of 3 mg/l BA and 20 % Spirulina platensis as a growth media resulted in a significant improvement in shoot proliferation. This combination produced the highest number of shoots (2.8 per explant) and leaves (6.3 per explant) similar with those containing MS media plus 20% extraction (2.9 per explant) and leaves (6.8 per explant). The longest shoots (2.97 cm) were obtained in each previous treatment. However, these shoots were similar with those produced from classical multiplication by MS according to ISSR analysis which scored 89.1 % of mono morphism percentage and 10.1 % polymorphism. The ISSR analysis shows the highest similarity index percentage for P5-P9 0.986301

    Hepatoprotective Effect of Methanol Extracts of Zingiber officinale and Cichorium intybus

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    The present work was carried out to investigate the hepatoprotective effect of ginger, chicory and their mixture against carbon tetrachloride intoxication in rats. Carbon tetrachloride treatment significantly elevated the alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase and gamma glutamyltransferase activities and the serum triglycerides and cholesterol concentration as compared to control group. It also increased RBCs counts and Hb concentration, total or differential leucocytes counts. However it decreased platelet counts, platelet distribution width, mean platelet volume, platelet larger cell ratio. Methanol extract of ginger (250 and 500 mg/kg) and chicory (250 and 500 mg/kg) given alone or mixed (1:1 wt/wt) significantly restored the carbon tetrachloride-induced alterations in the biochemical and cellular constituents of blood. No toxic symptoms were reported in doses up to 5 g/kg. Alkaloids and/or nitrogenous bases, carbohydrates and/or glycosides, tannins, flavonoids, saponins and unsaturated sterols and/or triterpenes are the main active constituents of their methanol extract. The hepatoprotective effect of ginger and chicory was also confirmed by the histopathological examination of liver tissue

    Global economic burden of unmet surgical need for appendicitis

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    Background There is a substantial gap in provision of adequate surgical care in many low- and middle-income countries. This study aimed to identify the economic burden of unmet surgical need for the common condition of appendicitis. Methods Data on the incidence of appendicitis from 170 countries and two different approaches were used to estimate numbers of patients who do not receive surgery: as a fixed proportion of the total unmet surgical need per country (approach 1); and based on country income status (approach 2). Indirect costs with current levels of access and local quality, and those if quality were at the standards of high-income countries, were estimated. A human capital approach was applied, focusing on the economic burden resulting from premature death and absenteeism. Results Excess mortality was 4185 per 100 000 cases of appendicitis using approach 1 and 3448 per 100 000 using approach 2. The economic burden of continuing current levels of access and local quality was US 92492millionusingapproach1and92 492 million using approach 1 and 73 141 million using approach 2. The economic burden of not providing surgical care to the standards of high-income countries was 95004millionusingapproach1and95 004 million using approach 1 and 75 666 million using approach 2. The largest share of these costs resulted from premature death (97.7 per cent) and lack of access (97.0 per cent) in contrast to lack of quality. Conclusion For a comparatively non-complex emergency condition such as appendicitis, increasing access to care should be prioritized. Although improving quality of care should not be neglected, increasing provision of care at current standards could reduce societal costs substantially

    Global economic burden of unmet surgical need for appendicitis

    No full text
    Background There is a substantial gap in provision of adequate surgical care in many low- and middle-income countries. This study aimed to identify the economic burden of unmet surgical need for the common condition of appendicitis. Methods Data on the incidence of appendicitis from 170 countries and two different approaches were used to estimate numbers of patients who do not receive surgery: as a fixed proportion of the total unmet surgical need per country (approach 1); and based on country income status (approach 2). Indirect costs with current levels of access and local quality, and those if quality were at the standards of high-income countries, were estimated. A human capital approach was applied, focusing on the economic burden resulting from premature death and absenteeism. Results Excess mortality was 4185 per 100 000 cases of appendicitis using approach 1 and 3448 per 100 000 using approach 2. The economic burden of continuing current levels of access and local quality was US 92492millionusingapproach1and92 492 million using approach 1 and 73 141 million using approach 2. The economic burden of not providing surgical care to the standards of high-income countries was 95004millionusingapproach1and95 004 million using approach 1 and 75 666 million using approach 2. The largest share of these costs resulted from premature death (97.7 per cent) and lack of access (97.0 per cent) in contrast to lack of quality. Conclusion For a comparatively non-complex emergency condition such as appendicitis, increasing access to care should be prioritized. Although improving quality of care should not be neglected, increasing provision of care at current standards could reduce societal costs substantially
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